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For anyone welding out there, Please keep this in mind. Any fumes present MIGHT be harmful when exposed to the heat of the weld.
There are numerous chemicals out there that change composition when heated. Tri-chlor-ethelyne, Carbon Tettrichloride, (great for de-greasing) are extremly dangerous to your health. I can not express this enough. My brother is dead because of Tri-chlor. It turns into Phosgene gas when heated above a certain point, and welding aluminum is more than enough to make it deadly. Aside from the fact that it can, and does go right thru the pores of your skin when you get it on your hands. (I have seem guys wash their hands with it) and I don't think any of them are alive anymore.
When you get gassed by the phosgene, it attacks the liver, and your liver cannot heal itself as most other body parts. Each time you are exopsed, you get damaged that much more, eventually making your liver hard as a rock. Having Alcahol (drinking) in your liver and breathing trichlor fumes can do terrible damage, too. The alcahol chrystalizes and plugs up your liver. (This is even faster) to kill you.
It takes fewer PPM of trichlor to be harmful than it takes to smell it, so you don't even want it in the same building if you can avoid it.
Many of the welders I used to work with are no longer with us because of this, and my liver is a bit on the hard side from it, too.
I am lucky to be alive after 25 years of welding aluminum in the factory where I worked. I still enjoy it, anyways, I am just more careful.
I guess soap and water would be much safer, just rinse it off good.
With TIG, wet is OK, it dries before you get there. With MIG, it can cause porosity, which greatly weakens the weld.

Well-Known Member

We use to use 1,1,1 tri-chlor all over the place at my airline but they pulled it years ago. I had heard that it's not even on the market anymore. It also causes hydrogen embrittlement (I think that's the term) when used on titanium, which aint good. We want to really know what we're doing when it comes to chemicals and cleaning. Those warning labels are there for a reason. Thanks for the tip.
Richard - Hanger7A

Active Member

I have never had the opprotunity to weld any titanium. As with anything else, I'm sure it has to be clean. Do you DC straight polarity, or reverse, like Stainless?
When we were welding around the trichlor at work, they didn't have to tell us ANYTHING, and they didn't either. They even had a guy whose job it was to lie to us about it! I can remember him saying; " I know you guys are concerned about the trichlor fumes, and you might feel a little dizzy, but it will pass, and you will be OK" He was a salary guy, and that was his job.
They do have a better policy now, but if you don't know what to ask, or what to look for, you are still at risk there.

Well-Known Member

The welder in my area says you weld it just like stainless. Also, the embrittlement I mentioned earlier happens at much lower temps than welding. This all came to light about a hundred years ago when I was sent up to scrub a DC-10 wing pylon and somebody jumped my stuff for using trich. Seems that the heat from the heat exchanger mounted over that big CF6 engine was enough to cause serious problems in the pylon titanium. Guess they hadn't heard of training a guy in those days. Anyway, the trich went the same route as the -10s - Gone and good riddance. This is why all the crap in walmart has china stamped all over it. They don't have job safety issues.
Richard Hanger 7A

Active Member

What? the stuff in Wal-Mart is made in China? I thought it was supposed to be made in America!
I know, no job saftey there, and not much pay, either. If we were to get into a really big war at this point, we would be screwed, no heavy industry to switch over to making heavy ammament, etc.

Active Member

I guess when Sam Walton died a lot of things changed at Wal-mart.
I was welding at a big tow-truck garage last week, and I smelled something. One of the mechanics was spraying a brake cleaner on a new brake drum. I asked to read the label, sure enough, there was perchloretheleyne, a very close chemical to tri-chlor. I waited a while till it blew out of the building. ( There was a large overhead door at each end, open.)
I don't know if it is still available, but cadbon tetrichloride is another bad one.
I really don't know if I am spelling those names right, but I think they are close